Treatment of gasoline



l tie 'ec. 1311.1, 1133 .loseph d. ilheniceh, capo, ML, assimmor totiniwersal Uill Products lilomp in chicago, Hit, a

corporation or Delae No Drawing.

AMDMIMWHOM Web a a a serial No. 3215M (cl. ii-ii) 23 Dias.

This invention relates to a method for improving the stability ofhydrocarbon distillates insofar as color and gum formation areconcerned.

More particularly the process concerns improved methods of preventingdeterioration of cracked gasolines which may be stored over relativelylong periods of time in contact with air.

The use of inhibitors to prevent the depreciation of olefin-containinghydrocarbon distillates such as cracked gasoline has been practiced.Such compounds as alkyl-substituted phenols, aminophenols, fractions ofwood tar distillates, etc., have been added to cracked gasoline inrelatively minor quantities, of the order of il.0il1-0.l0% to inhibitthe formation of objectionable oxidation products and prevent loss ofcolor and antiknock properties of said gasolines during storage periods.The use of inhibitors has replaced or supplemented such forms ofrefining as acid-treating, clay-treating and the like. The

result has been a material saving in refining costs as well astheconservation of substantial amounts of gasoline which were formerlylost in the refining steps.

The present invention ofiers a means of improving the inhibitingproperties of gasoline gum inhibitors and of eiiecting material savingsin the quantities of such materials which may be required adequately topreserve the valuable properties ofgasoline.

In one specific embodiment the present invention is a method fortreating olefin-containing hydrocarbon distillate and particularlycracked gasoline to preserve the valuable properties thereor whichcomprises adding to said distillate a gasoline gum inhibitor togetherwith a relatively or quantity of an aryl-substituted-alkylene diamine.

The preferred compounds have the general wherein R is an aryl group, Rmay be an alkyl cup or a hydrogen atom, R" may be an aryl group or ahydrogen atom, a: may in zero or an integer and m is an integer.Representative compounds are diphenyl ethylene diamine and diorthotolylethylene diamlne.

The compounds are used in combination with kno gasoline gum inhibitorssuch as N-substituted alkyl aminophenols, alkyi phenols, substitutedphenol ethers, fractions oi wood tar distillate such as those boiling inthe range of Mil-280 0., and others. The compounds of this invention maybe added to the gasoline separately or simultaneously with the guminhibitor, or may be mixed with the'gum inhibitor and the mixture addedto the gasoline.

The quantity of aryl-substituted-alkylene diamine used in the gasolineis of the order of 0.000l-0.01%. The exact quantity required is afunction of the gum inhibitor with which it is used and of the gasolineas well as the desired stability of the gasoline treated. The compoundsof this invention are not of themselves gum inhibitors and the efiectobserved is not therefore such as might be expected by the mixing of twogasoline gum inhibitors.

When the present types of compounds are added alone to cracked gasolinein amounts up to approximately 0.1%, little or no increase in the oxygenbomb induction period is to be 'observed and storage tests indicate thatno protection is obtained for the gasoline under storage conditions.However, when a gum inhibitor is also added, the induction period with agiven quantity of the gum inhibitor is markedly increased and with themore efiective compounds of this invention, frequently more than half ofthe guminhibltor can be replaced by considerably less than an equalweight per cent of the compounds without suffering a loss in inhibitorpotency. This will be brought out more fully in the examples to be givenlater.

The compounds of this invention are not necessarily exactly equivalentin their effects and it should be understood that they cannotnecessarily be used to replace one another in the composite inhibitorwith equal efiects either on a weight or chemically equivalent basis.

The following example is given to illustrate the usefulness andpracticability of the process, but should not be construed as limitingit to the exact conditions or compounds given therein.

A Pennsylvania cracked gasoline containing 0.01% of N-butyl aminophenolinhibitor had an induction period of 330 minutes by the oxygen bombtest. When 0.01% oi diphenyl ethylene diamine was added thereto, theinduction period was increased to 425 minutes. When 0.01% ofdiorthotolyl ethylene dlamine was added to the inhibited gasoline, theinduction period was increased to 385 minutes.

I claim as my invention:

1. A method of treating olefin-containing hydrocarbon distillate toprevent depreciation thereof which comprises adding to said distillateFl Ii wherein R is an aryl group and a: is an integer.

5. method of treating craclred gasoline to prevent depreciation thereofwhich comprises adding thereto a gasoline gum inhibitor and a compoundof the following general structure:

R a N'om-(cH: ..-N

n 11 wherein R and R are aryl groups and a: is an integer. G. A methodof treating cracked gasoline to prevent depreciation thereof whichcomprises adding thereto a gasoline gum inhibitor and a compound of thefollowing general structure:

a R a I N-(CHz)=-C(CHz)r-N I i1 n wherein R is an aryl group, R is analkyl group and a: is an integer.

'l. A method of treating cracked gasoline to prevent depreciationthereof which comprises adding thereto a gasoline gum inhibitor and acompound of the following general structure:

. R a" N ora).-o-' on, i-i n l n wherein R andR" are aryl groups R is analkyl group and an is an integer.

8.,A method of treating cracked gasoline to prevent depreciation thereofwhich comprises adding thereto a gasoline gum inhibitor and a minorquantity of a diphenyl ethylene diamine.

9. A method of treating cracked gasoline to prevent depreciation thereofwhich comprises adding thereto a gasoline gum inhibitor and an amount ofan aryl-substituted-alkylene diamine within the limits of approximately0.0001-0.01% by weight of the gasoline treated.

10. A method of treating cracked gasoline to prevent depreciationthereof which comprises adding to said gasoline a gasoline gum inhibitorin amounts of approximately 0.001-0.1% and an amount of anaryl-substituted-alkylene diamine within the limits of approximately0.0001-0.01%

by weight of the gasoline treated.

11. A method of treating cracked gasoline to prevent depreciationthereof which comprises adding to saidgasoline a gasoline gum inhibitorconsisting of an N-substituted alkyl aminophenol and anaryl-substituted-alkylene diamine.

all

arose-rs it. A method of treating cracked gasoline to preventdepreciation thereof which comprises adding to said gasoline a gasolinegum inhibitor consisting of a wood tar fraction boiling within thelimits of approximately 240280 C. and an aryl-substituted-alkylenediamine.

it. An inhibitor for cracked gasoline comprising essentially a mixtureof a gasoline gum inhibitor and an aryl-substituted-alkylene diamine.

M. an inhibitor for cracked gasoline comprising essentially a mixture ofa gasoline gum inhibitor and an aryl-substituted-allrylene dlaminehaving the following general structure:

1r N-cmom),-N

wherem. ht and it are aryl groups and :c is an integer.

iii. an inhibitor for cracked gasoline comprising essentially a mixtureof gasoline gum inhibitor and an aryl-substit-uted-allrylene diaminehaving the following general structure:

wherein it is an aryl group, R i an alkyl group and is an integer.

1d. inhibitor for cracked gasoline comprising essentially a mixture of agasoline gum inhibitor and an aryl-suhstituted-alkylene diamine havingthe following general structure:

n R n" /N-(CHz):(:J-(CH2)=' 11 11 wherein R and R" are aryl groups, R isan alkyl group and r is an integer.

17. An inhibitor for cracked gasoline which comprises essentially e.mmture of a gasolin gum inhibitor and a diphenyl ethylene diamine.

' 18. An inhibitor for cracked gasoline which comprises essentially amixture of a wood tar dis- 1 tillate boiling within the limits ofapproximately Edd-280 C. and an aryl-substituted alkylene di- 19. An.inhibitor for cracked gasoline which comprises essentially a mixture ofa gum inhibitor with a diorthotolyi ethylene diamine.

20. An inhibitor for cracked gasoline which comprises essentially amixture of a wood tar distillate gasoline gum inhibitor boiling withinthe limits of approximately Will-280 C. with a diphenyl ethylenediamine.

21. A composition of matter useful for inhibiting the oxidation ofunstable organic substances such as olefin-containing hydrocarbondistillate which comprises a mixture of an antioxidant with anaryl-substituted alkylene diamine.

22. In the art of stabilizing olefinic distillates against deteriorationby the addition of gum inhibltors thereto, the method of increasing thegum inhibiting potency of the inhibitor which comprises incorporatinginto the oleflnic distillate, in addition to the gum inhibitonarelatively small amount of an aryl-substituted alkylene diamine.

23. A stabilizing agent suitable for retarding gum formation in olefinicdistillates comprising a phenolic gum inhibitor and an amount of anarylsubstituted alkylene diamine such as to increase the inhibitingpotency of the phenolic inhibitor.

JOSEPH A. CHENICEK.

